Baltic alliances: Symbiosis as the engine of phytoplankton diversity and nitrogen cycling

SYMBALTIC is a collaborative project aiming to understand the mechanisms behind Baltic Sea phytoplankton population dynamics as a predictor for the changing global ocean. The project aims to build on a partnership made through TREC, which led to a recent discovery of a tripartite symbiosis involving Chaetoceros, that has both seasonal recurrence and potentially inhabits the entire Baltic Sea. We will systematically uncover the factors influencing the seasonal biogeography as well as develop the consortium into a tractable model system for future experiments.

Objectives

1. Map distribution, seasonality and environmental drivers of Chaetoceros holobionts
2. Establish Chaetoceros cell cultures and co-cultures for understanding of life cycle dynamics
3. Determine nutrient and carbon fluxes, and their differences between the Chaetoceros cell cultures and the samples captured in nature